Role of stem cells in development of allergies and asthma

AllerGen researchers have published a new review in Mucosal Immunology (a high-impact journal of the Nature group) that outlines the contributions of blood cell production by the bone marrow and “in situ” blood cell development that occurs at a local site of injury and inflammation, highlighting the importance of these processes in allergic inflammation in particular.

The review examines previous and emerging studies demonstrating that hemopoietic progenitor cells—stem cells that can give rise to many other types of blood cells—play a key role in the immune response that causes allergies and asthma.

Hemopoietic progenitor cells populate the blood marrow and related blood-forming organs, where they “differentiate” to produce specialized blood cells (such as eosinophils and basophils) that are then recruited to the body’s tissues once an immune response has been triggered. However, research has shown that these progenitor cells can actually migrate from the bone marrow to the airways and other tissues before differentiation occurs, after local stimulation by an allergen (e.g., pollens in the nose or lungs, foods in the gastrointestinal tract) to cause inflammation.

“This review represents a wonderful collaborative effort by several research groups,” says AllerGen’s Scientific Director Dr. Judah Denburg, head of the Division of Clinical Immunology & Allergy at McMaster University and one of the paper’s co-authors. “From ideas first generated through observations in allergic patients begun several decades ago in my laboratory, more recent, detailed research in both animal models and human subjects now fill in the ‘blanks’ and offer much more extensive explanations of the cellular and molecular mechanisms through which bone marrow-derived stem cells participate in the development and persistence of allergies and asthma. This research field is already leading to a better understanding of how to select more definitive treatments for allergic rhinitis and asthma, and paves the way to discovery of diagnostic biomarkers and predictors of allergy and asthma in early life,” he adds.

“This is a wonderful example of how astute observations made by clinical scientists can guide basic scientists to clarify mechanisms that could lead to new therapies,” comments Dr. Kelly McNagny, co-author and Professor of Medical Genetics at The University of British Columbia. “This showcases the value of Networks like AllerGen to promote scientific cross-fertilization and collaboration.”

AllerGen trainee and the paper’s first author Dr. Claudia Hui (McMaster University), and Dr. Mark Siracusa (Rutgers New Jersey Medical School) are also authors of the paper.